Just when you thought that shiny new aftermarket upgrade would finally mean the difference between reaching the podium and hanging out mid-pack, you still struggle to get up front. Unfortunately, the expected boost in performance got left behind - but a solution exists.

An EFI tuner offers an excellent way to fine tune your dirt bike and allow it to run at full capacity but you can also really mess things up if you install it incorrectly or do not have it properly tuned.

Stock bikes do not feature this device pre-installed and not every bike needs one.

If you ride a 2-stroke or any carbureted bike you do not need a tuner. Actually, you can't have a tuner. Well you can but it won't hook up to anything and will simply add extra weight to your dirt bike. So forget it.

If you have a fuel injected dirt bike but have performed no engine modifications or exhaust upgrades or you don't use race gas, then you don't necessarily need an EFI tuner but might find some use from one.

You likely won't see much in terms of performance gains however you can better tune for ride-ability, weaker gas, elevation changes, trail vs. track riding or even tune out/flame out/stall situations. For example the early EFI bikes sometimes suffered from stalling issues and other issues a tuner could help even without any performance mods done to the bike.

Generally speaking though, an EFI tuner helps bridge any gaps between upgrades and potential performance so if you have done any of the following an EFI tuner can help you get the most of the possible gains in operation:

  • Exhaust upgrade (full or slip-on)
  • Intake upgrade
  • Big bore upgrade
  • High compression piston
  • Race gas
  • Crank or rod stroke changes
  • Changes to the flywheel (slight benefits)

Think of it this way, any upgrade that alters the fuel to air ratio benefits from a tuner that makes the necessary compensation adjustments - meaning getting the most out of the potential the upgrades offer. The more upgrades, the better your argument for buying a tuner.

What is an EFI Tuner?

Don't mistake the ECU with the EFI tuner. All bikes have an ECU (Engine Control Unit) which controls the EFI (Electronic Fuel Injection) system. You cannot adjust the EFI system without an aftermarket ECU or ECU tuner or a standalone EFI tuner. An EFI tuner adjusts only the fuel delivery. An aftermarket ECU or Programmable ECU Does both fuel delivery (on EFI bikes) and ignition timing modification and few other things. That's a much larger and more complicated process than we will discuss here.

The EFI tuner modifies the air and fuel commands in the stock ECU. The ECU is similar to the CDI box on carbureted bikes only it controls both the ignition and the fuel, whereas the CDI works the ignition while the carb and jetting handles fuel/air. So the ECU is the brains, the EFI tuner adjusts the brains (ECU's) fuel air control just as changing jets in a carburetor would. By working with any and all of the engine modifications noted above an EFI tuner contributes to:

  • Increased power
  • Better throttle response
  • Better torque

Once installed the tuner easily adjusts to maximize performance. The EFI box remains with the bike (usually under the seat) but the tuner or computer program that attaches to the box gets removed after completing the necessary adjustments. If adding extra weight worries you don't worry. The performance gains offered by the tuner easily compensate for the few ounces of added load. Most EFI tuners install pretty easily and have step-by-step directions. Since each make and model has their own process we won't cover an actual "How To Install an EFI tuner." Once in, many tuners feature a "plug and play" design allowing you to hook the device up between the ECU and the throttle body's electronics. The tuner identifies and makes the necessary adjustments.

If you invest in one of the more advanced systems used by the factory teams, unless you have a background as a mechanic and have previously worked with tuners, we highly recommend using a professional mechanic to make the adjustments while using a dyno. You can create some havoc inside the engine if you make the wrong adjustment and then end up down a rabbit hole trying to find your way back out.

Honda, Yamaha and Kawasaki offer OEM tuners for their models but for all others you will need to buy aftermarket. Check out our suggestions for EFI tuners:

EFI Tuners don't come cheap. However, if you have upgraded any parts that directly affect the fuel/air ratio but you do not feel much difference in overall performance installing an EFI tuner might provide the solution to any buyer's remorse and remove the unintended handcuffs on your system.

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Written By: AndrewT